apt-get isntall error, mmap run out of room, urgent

[eric]

Dear Debian users:
  When I used apt-get update, I get the following error at end:

Fetched 2374kB in 45s 
(52.7kB/s)                                              Reading Package 
Lists... Error!
E: Dynamic MMap ran out of room
E: Error occured while processing tomcat (NewVersion1)
E: Problem with MergeList 
/var/state/apt/lists/http.us.debian.org_debian_dists_testing_contrib_binary-i386_Packages 

E: Unable to write mmap - msync (14 Bad address)
E: The package l

hope to see some advanced users' help, and thank in advance, eric  /* 
very urgent */